Method and apparatus for binding perforated sheets



June 12, 1962 M. D. LEVITAN 3,038,180

METHOD AND APPARATUS FOR BINDING PERFORATED SHEETS Filed Feb. 23, 1960 e Sheets-Sheet 1 INVENTOR aur/ce D. Lev/fan BY %TTORNEYS June 12, 1962 M. D. LEVlTAN METHOD AND APPARATUS FOR BINDING PERFORATED SHEETS Filed Feb. 25, 1960 6 Sheets-Sheet 2 INV ENTOR Maw/v c e 0.1 ezr/ fan fl ZW A ORNEYS I June 12, 1962 M. D. LEVITAN 3,038,130

METHOD AND APPARATUS FOR BINDING PERFORATED SHEETS Filed Feb. 23, 19 0 e Sheets-Sheet 3 IN VENTOR Mal/Mae & Lev/fan A ORNEYS M. D. LEVITAN June 12, 1962 METHOD AND APPARATUS FOR BINDING PERFORATED SHEETS 6 Sheets-Sheet 4 Filed Feb. 23, 1960 A INVFNTOR Maumc'e Q L ear/fan w AL'ITORNEYS ww a A June 12, 1962 M. D. LEVITAN METHOD AND APPARATUS FOR BINDING PERFORATED SHEETS 6 Sheets-Sheet 5 Filed Feb. 23. 1960 INVENTOR V Maurice D. L ev/Ian ATTORNEYS June 12, 1962 M. D. LEVITAN 3,038,180

METHOD AND APPARATUS FOR BINDING PERFORATED SHEETS Filed Feb. 23. 1960 6 Sheets-Sheet 6 INV EN T OR Mdar/c'e 0 Z aw fan ATTORNEYS States The present invention relates to a method and apparatus for binding a plurality of sheets of paper or the like punched along one edge thereof. More particularly, the invention relates to an improved method and apparatus adapted to bind a stack of perforated sheets with thin non-self-supporting heat scalable plastic material.

As those familiar with the art of binding loose sheets are aware, numerous materials and methods of binding have been employed in the past. Commonly practiced methods include binding sheets with meta-l staples, metal rings, and binding elements composed of plastic. To my knowledge, successful binding of perforated sheets by plastic binding elements has, inthe past, been limited ot methods and apparatus employing relatively stiff, selfsupporting plasitc materials for the binding element. However, the least expensive forms of plastic materials comprise the extremely thin, relatively soft and non-selfsupporting, plastic materials such as, for example, films of vinyl or polyethylene. I have, in accordance with the teachings of the present invention, provided a method and apparatus for carrying out such methods for satisfactorily binding a plurality of perforated sheets inexpensively with such heat scalable, non-self-supporting plastic.

Broadly speaking, the method of binding envisaged'by the present application comprises the step of initially stacking a plurality of sheets of paper or the like with at least one aperture adjacent an edge thereof in alignment with a similar aperture in the remaining sheets; projecting a strip of thin generally flexible plastic material through the aligned perforations from one side of the stack of sheets; wiping the portion of the plastic material projecting from the other side of the stack of sheets laterally along the surface of the other side; wiping the said projecting portion over the adjacent edge of the stack of sheets and deflecting it downwardly across the edges of the stack of sheets; wiping the projecting finger of plastic laterally toward the portion of the finger projecting into the perforationon the said one side of the stack of sheets, and thereby forming a loop; and heat sealing the loop thus formed at a point immediately adjacent entry of the finger into the perforations and said one side of the stack of sheets. By thus wrapping the flexible non-self-supporting plastic ribbon or finger closely around the edge of the sheets to be bound, a comparatively tight loop of binding material is provided. The method contemplates, of course, the simultaneous wrapping of a plurality of fingers of plastic through a corresponding plurality of pierced apertures to provide, for example, a plastic binding of a large number of loops.

In performing the method outlined above, on a rapid, production-line basis, it is preferred that mechanized apparatus be provided rather than attempt all of the steps manually. The present application illustrates one commercial form of apparatus that has proved satisfactory in the performance of the method outlined. The apparatus comprises a table arranged for the accumulation of a number of sheets of paper or the like perforated along one edge. A series of vertically upstanding probes are provided, each of which probes has a cross-section somewhat less in area than the cross-sectional area of the individual perforations. Upon stacking of the plurality of sheets upon the machine table mechanical means 3,038,180 Patented June 12, 1962 is provided for inserting one of said probes vertically upwardly through each "of the perforations intended to contain a binding ribbon or finger. Each of the probes is hollow and automatic feed means is provided for projecting a thin ribbon of plastic material upwardly through the tip of the probe. By projecting the probe upwardly completely through the stack of perforated sheets the nonself-supporting plastic is assured of complete penetration through the sheets. Upon movement of a strip of the plastic material upwardly through the stack of sheets, the probes are withdrawn leaving an upstanding finger of plastic projecting through each perforation. A bar is then dropped upon the uppermost sheet of the stack and is slid generally horizontally against the upwardly projecting fingers of plastic wrapping the fingers over the edge of the stack and downwardly. A sealing bar is then moved generally in the plane of the stack of sheets immediately below the stack pinching the downwardly wrapped and projecting finger of plastic against the plastic as it projects upwardly through the individual perforations. In the apparatus illustrated, heat is applied by the sealing means causing a permanent sealing of the loop at the pinched area. In mechanizing the apparatus of the present invention to form the method in a rapid manner, a motor-driven cam shaft is provided for sequentially actuating the mechanical means described. In one specific embodiment of the apparatus, a complete cycle, including the time necessary to apply the sealing heat, may satisfactorily comprise approximately six seconds, thereby permitting the binding of approximately ten books or stacks of sheets per minute. The speed of operation of the apparatus is in no way aifected by the number of loops of binding material formed and, in the preferred form of the invention, this may readily be adjusted to suit the particular binding problem.

It is, accordingly, an object of the present invention to provide a novel method of binding a plurality of perforated sheets together.

Another object of the invention is to provide a method of binding a plurality of perforated sheets together which comprises forming a loop of thin non-self-supporting plastic material through at least one of the perforations of each sheet.

A vfurther object of the present invention is to provide a novel method of binding a plurality of perforated sheets of material with thin non-self-supporting plastic which comprises projecting a length of non-self-supporting plastic material through theapertures to be bound, wrapping the projecting plastic material backwardly upon itself around the surface of the sheet material to be bound and permanently heat-sealing the loop thus formed.

Yet another object of the present invention is to provide an improved and highly efiicient apparatus for binding books or the like.

Yet a further object of the invention is to provide an automatic completely mechanized apparatus for binding a plurality of perforated sheets with loops of flaccid, nonself-supporting heat-sealable plastic ribbon material.

A feature of the invention resides in the provision of apparatus comprising a plurality of sequentially operated loop-forming members sequentially driven and timed from a single source of power.

Another feature of the invention resides in the provision of a loop-forming machine for binding a plurality of perforated sheets with a flaccid, non-self-supporting ribbon of plastic material and having means for resiliently moving the table supporting the stack of sheets to permit an extremely snug loop of plastic to be formed.

Still other and further objects and features of the present invention will at once become apparent to those skilled in the art from a consideration of the attached specification and drawings, wherein a preferred form of 3 the invention is shown by way of illustration only, and wherein:

FIGURE 1 is a plan view of the apparatus constructed in accordance with the present invention;

FIGURE 2 is a side-elevation of the apparatus shown in FIGURE 1 as viewed from the'left in FIGURE 1;

FIGURE 3 is a front-elevation of the apparatus in FIGURE 1;

FIGURE 4 is a sectional view taken along the line IV--IV of FIGURE 3 illustrating the simultaneous positioning of the loop-forming mechanisms.

FIGURE 5 is a cross-sectional view taken along the line V-V of FIGURE 3 illustrating in detail the actuation of the probe-lifting mechanism of the Present invention',

FIGURE 6 is a cross-sectional view taken along the lines VI--VI of FIGURE 3 illustrating in detail the feeding apparatus governing movement of the flaccid plastic material employed in the binding apparatus of the present invention;

FIGURE 7 is a cross-sectional view taken along the line VII--VII of FIGURE 3 and showing, in greater detail, the construction of the mechanism actuating the pusher bar of the present invention; and

FIGURE 8 is a cross-sectional view taken along the line VII-VII of FIGURE 3 and illustrating in detail the construction and operation of the heat-sealing bar employed in .the apparatus of the present invention.

As shown on the drawings:

As may be seen from a consideration of the drawings, and in particular, FIGURES 1, 3 and 4, apparatus is provided for binding a stack of perforated sheets 10, having perforations 10a along one edge 11 thereof. The stack is placed flat upon table 12 and squared up thereon against the left-hand edge thereof as viewed in FIGIRE 4 against upstanding retaining fingers 13. The sheets are positioned with the perforations 10a thereof, shown as rectangular in the present instance, facing an area between the adjacent retaining fingers. The horizontal surface of the table 12 between the adjacent retaining fingers 13 and beneath the perforations in the sheets is notched or cut away, as at 14, to permit the upward passage of a series of feeder probes 15. Immediately above the stack of sheets 10 a pusher bar 16 is pivotally mounted to a pusher bar arm 17 at pivot 18 for movement in the direction of arrow 19. The pusher bar 16 carries fingers arranged to pass between adjacent retaining fingers 1'3 and having a width greater than the width of the individual perforations.

Broadly speaking, it is the function of the apparatus to eject, via probes 15, a plurality of strips of generally flaccid, non-self-supporting plastic ribbon upwardly through the perforations 1 1 so that the plastic ribbons project a substantial amount above the top of the stack 10. The pusher bar 16 then moves in the direction of arrow 19 such that the fingers 20 deflect the upstanding ribbon of plastic, generally indicated at 21, to the left as viewed in FIGURE 7. The pusher bar 16 is permitted to move to the left sufliciently far to allow the fingers 20' to drop downwardly over the edge of the stack of sheets 10 causing the ribbons of plastic material to be bent downwardly snugly against the left-hand edge of the stack of sheets. A sealing cut-off bar pivoted about the pivot point 26 then moves in the direction of arrow 27 to pinch the downwardly projecting end of the plastic ribbon to the right against the portion of the ribbon immediately below the perforations 10a. Both pieces of ribbon are moved transversely to the right as viewed in FIGURE 8 against a heating element 30, preferably of the resistive type, embedded beneath a dielectric surface, preferably composed of a plastic material. The bar 25 preferably comprises a round wire of extremely small diameter and upon the application of heat to the pinched ribbon of plastic, the wire acts to squeeze off or cut off the sealed loop so that upon withdrawal of the stack 4 of sheets 10 from the table 12' it will be bound in a plurality of soft plastic loops permanently sealed.

The apparatus for accomplishing the generally discussed operations above will now be more specifically described. The apparatus illustrated is constructed to provide a complete binding cycle of approximately six seconds. In other words, the apparatus is designed to provide a binding of approximately ten books per minute. It is further desired that the operation of the machine be at least semi-automatic to thereby reduce to a minimum the manual manipulations necessary.

In the embodiment of the invention shown in the drawing, a single motor 35 is mounted on the table support 36. The motor 35 drives a single cam shaft 37 by means of a chain drive 38 and a reduction gearing that provides one revolution of the cam shaft 37 in six se/conds. As mentioned above, the six second period is a satisfactory one. However, it will be understood by those skilled in the art that the length of the period may be varied, if desired, by changing the speed of rotation of the motor or the gear ratio of the reduction gearing. In the arrangement shown it is desired that the cam shaft 37 complete one revolution for each cycle of binding. Accordingly, a conventional switch is preferably provided for manual operation by the machine operator (by foot pedal or the like) for energizing the motor 35. The power to the motor is automatically cut off upon completion of rotation of the cam shaft 37 through 360. Alternatively, a one-revolution clutch may be provided in the chain drive 38 to permit cycling of the apparatus through a single revolution for each initiating movement by the operator. Such one-revolution motor controls and/or one-revolution clutches are conventional in nature and are not illustrated. The specific construction of these devices forms no part of the present invention.

As above mentioned, it has been found that a Six-second cycle of operation is satisfactory. For example, in a six-second cycle, it is proposed that immediately upon initiation of the cycle and consequent energization of the motor 35 and rotation of cam shaft 37, the slight projection of ribbon 21 remaining from the previous operation is withdrawn into each of the probes 15. The operator positions the book on the work table during the period of l to 2.5 seconds following motor energization and at the end of 2.5 seconds, the probes 15 are projected upwardly through the perforations 10a. Immediately thereupon, and during the period of from approximately 2.6 to 3 seconds, tape is fed through the probes 15 upwardly above the top surface of the stack of sheets. At 3.0 seconds the probes are lowered below the stack of sheets leaving an upwardly projecting ribbon or tape projecting through the perforations in the sheets. At this point, and during the time interval of 2.0 to 3.5 seconds, the pusher bar 16 is advanced to the left in the direction of arrow 19 wrapping the upstanding ribbons 21 over the left-hand edge of the stack of sheets. At 3.5 seconds the sealing bar 25 moves toward the right in the direction of arrow 27 into sealing contact with the looped ribbon 21 and starts a timer directing electrical current to the resistive type heater 30 for a period approximating 2 seconds. After approximately 5.8 seconds the seal bar 25 is moved backwardly to the left and the pusher bar 16 is moved backwardly toward the right, all as viewed in FIGURE 3, at which time the bound stack of sheets may manually be withdrawn from the table 12.

The above cycle is readily accomplished in accordance with the apparatus illustrated in the drawings of the present application. As shown in the drawings, and particularly FIGURE 4 thereof, the probes 15 are moved in an upward direction by means of probe selector bars 51 which are slidably mounted within a longitudinal guide 52 pivoted at its ends 53 in the support plate 36. An over-center spring 54 seated in a slot 55 in each selector bar 51 maintains the bar in the left-hand position as shown in FIGURE 4 or, upon manual manipulation toward the right as viewed in that figure, in an extreme right-hand position in which the left-hand end of the bar 51 is withdrawn from contact with the abutment 56 on the probe 15. The selector bars 51 are each moved upwardly through a leaf spring 57 carried by a yoke 58 rigidly secured to a pivot bar 59 which'in turn rigidly carries a cam follower 60 having a roller 61 thereon for cooperation with probe lift cam 50.

The weight of the yoke 58 and cam follower 60, coupled with the weight of the selector bars 51 and the probes 15, maintains the roller 61 against the peripheral surface of the cam 59. Upon rotation of the cam 50 in the counterclockwise direction by the cam shaft 37, the probes 15 contacted by selector bars 51 are first lifted by lobe 50a, subsequently dropped and then again raised by lobe 50b.

In FIGURE 4 of the drawings, the cam shaft 37 and the cams mounted thereon are shown in the position immediately at the start of a cycle of operation. Accordingly, the probes 15 are in their lowermost position. Upon rotation of the cam 50 in the counterclockwise direction to a point at which the roller 61 rides upwardly on lobe 50a, the parts will achieve the position illustrated in FIGURE 5. As there shown, the individual probes 15 are lifted upwardly in the stationary guide blocks 62 into a position projecting up through perforations a in the stacked sheets 10. In this position-feed rollers 63 are in contact with the main feed roller 64 and rotation of the main feed roller 64 will cause rotation of the rollers 63 causing frictional movement of the ribbon 21 in each probe 15, upwardly upon counterclockwise rotation of the main roller 64 and downwardly upon clockwise rotation of roller 64.

In the cycle above described, initial operation provides lifting of the probes during the first second of cycle operation. During this period, the probe rollers 63 contact roller 64 and the roller 64 is operated in the clockwise direction a short distance to withdraw the ribbon 21 projecting slightly above the upper end of the probe 15 as a result of the preceding operation, back into the probe 15 to a proper subsequent feed length of ribbon. Such clockwise rotation of the roller gear 65 which is in turn caused by downward oscillation of the rack 66 pivotally mounted at 67 and actuated by link 68 and cam follower 69. The follower 69 is biased in any conventional manner, such as for example by spring '71 so that the roller 71 thereof contacts feed cam '75. As may be seen in FIGURE 4 the initial position of the parts is such that the gear 65 is in a generally neutral position. Upon rotation of the camshaft 37 in the counterclockwise direction until the roller 61 of the probe cam Silt moves upwardly to elevate the probes, the lift segment 76 of the cam 75 pivots the follower 69 in the counterclockwise direction causing clockwise rotation of gear 65 and the main feed roller 64 to lower the ribbon 21.

Following the lowering of the ribbons 21, the rack 66 is maintained in the position above described by portions 77 of the cam 75. However, since the roller 61 of the probe control passes over the portion 50:: of the probe cam 51), the probes are lowered so that the feed roller drive between rollers 63 and 64 is discontinued until the probes 15 are subsequently raised by operation of the cam lobe 50b. Simultaneously with this raising action, the decreasingcam slope 723 of cam 75 permits clockwise rotation of the cam follower 69 by operation of spring '70 to cause a counterclockwise rotation of gear 65 and roller 64 with resultant upward movement of a ribbon 21 above'the top surface of the stacked sheets 10. This upward movement is, due to the fact that the probes 15 are at this time projecting up through the perforations 111a, unimpeded by the sheets themselves. Since, as above mentioned, it is desired to use the relatively inexpensive thin gauge heat sealing materials such as polyethylene film, the generally limp or flaccid nature of such materials requires that the point of ejection of the ribbon be substantially at the upper surface of the stack of sheets so that the uppermost edge of the ribbon 21 will not catch against the edge of the perforation 10a of an upper sheet in the stack to thereby prevent proper ejection of the ribbon above the surface of the stack.

Following the operation of feeding the ribbons 21 upwardly through the perforations 10a, with the stack 16 in position against fingers 13 of the table 12, the pusher bar 16 which is gravitationally biased downwardly against the top surface of the stack 10 is moved toward the left in the direction of arrow 19. This movement .is accomplished by cam 80 which actuates cam follower 81 pivotally mounted at 82 and connected to pusher bar arm 17 via a link 83 and an adjustable leverage connection 84. Upon rotation of the cam 81? in the counterclockwise direction for approximately 3 seconds, or half the cycle of operation, the surface 80a of cam 31 con tacts roller 85 causing counterclockwise rotation of c-am follower 81 and resultant movement of the pusher bar arm 17 in direction of arrow 19 causing the fingers 2G to contact the upstanding ribbons 21 bending them toward the left. Continued motion of the pusher bar 16 and the fingers 20 will cause the fingers 20 to pass between the upstanding fingers 13 of the table 12 and drop down- .wardly. into the dotted line position shown in FIGURE 7 in which the ribbon or tape 21 is looped generally vertically downwardly upon itself. Stops 16a cooperate with blocks 12a to limit the downward movement of fingers 20.

Immediately following the downward dropping movement of fingers 20, cam 91 best shown in FIGURE 8, pivots the sealer bar 25 in the clockwise direction about its pivot 26 by action of the ram a against the roller 25a. This movement will position the bar in the solid line position shown in FIGURE 8 in which the wire 25!) pinches the looped ends of the ribbons 21 against the resistance heater element 30 which is dielectrically insulated from the cut-off wire 25b by a plastic coating 311a. In order to provide a snug loop, it is desired that the stack of sheets 10' be moved toward the right as shown in FIG- URE 8 immediately prior to the pinching of the ribbons ends. This may be accomplished by providing a stop 91 on the heat sealing bar 25. The stop 91 contacts the fingers 1 3 of the table 12 causing the table 12 to slide toward the right a slight amount prior to contact of the cut-off wire 25b with the looped ribbon 21. This, of course, requires that the table12 be slidably mounted, for example, in the manner illustrated at 92 in FIGURE 1. A spring 93 normally biases the table into its left-hand position in alignment over the probes 15, as particularly illustrated in FIGURE 6. Obviously, the snugness of the loop formed in the ribbon 21 may be controlled by adjustment of the thickness of the stop 91.

Simultaneously with the movement of the sealing bar 25 toward the right as viewed in FIGURES 4 and 8, a switch, not shown, energizes the resistance heater 30 for a timed cycle, preferably approximately 2 seconds. The timing cycle may, of course, be shortened or lengthened at will, depending upon the heat sealing characteristics of the particular ribbon or tapelmaterial. The switch may be of any conventional form actuatable by a cam follower,.such as for example, the heat sealing bar 25 itself, and for this reason is not specifically illustrated.

Upon completion of the sealing cycle, the bar 25 is released by the lowering ramp 9% of cam 96 permitting counterclockwise oscillation of the lever 25 under the influence of any conventional bias, for example, spring 95. The bound sheets 10 may then be withdrawn from the table 12. At this same time, the pusher bar 16 is returned toward the right as viewed in FIGURE 4 by action of the spring 81a shown in FIGURE 4. The pusher bar may be lifted about its pivot 18 for insertion of the next stack of sheets 16 and then lowered upon the top surface of the stack 10 to provide a sheet clampingforce during the next succeeding cycle.

It will be clear to those skilled in the art that modifications may readily be made in the apparatus above described without departing from the novel concepts of the present invention. For example, the amount of time given the individual operations of the cycle may be varied by modification of the contour of the cams 50, 75, 80 and 90. Likewise, mechanical adjustments may be provided between the sealing bar and the portion thereof carrying wire and in the position of the pusher bar 16 relative to the link carrying it to compensate for variations in the ribbon material and the number and thickness of perforated Sheets being bound. Similarly, it will be clear that the apparatus may be run continuously in a series of repeating cycles without requiring initiation of the individual cycle by the operator by providing a continuous uninterrupted drive to the cam shaft 37.

In the embodiment of the invention illustrated, the

heat scaling is accomplished by cut-off wire 25b co-operating with the heat-resistive element 30. It will be clear that the position of these parts may be reversed. In other words, the heating element may be carried by the bar 25, with the unheated, cut-off wire being positioned beneath the table 12.

While I have herein shown the plastic ribbons as being projected upwardly through the stack of sheets, it may readily be understood that the machine may be inverted and that the plastic ribbons may be projected downwardly through the stack of sheets as well, and that various other variations in the invention may be attained without departing from the spirit and scope of the novel concepts thereof as defined by the claims appended hereto.

I claim as my invention:

1. Apparatus for binding a stack of sheets each having at least one perforation therein adjacent an edge thereof, a support for said stack, probe means insertable in the perforation of said stack of sheets for guiding a heatsealable ribbon through said stack of sheets, means feeding a ribbon of said material through said probe to project said material beyond one side of said stack, means slidable along said one side of said stack for laterally deflecting the projecting end of the ribbon toward the edge of said stack, means subsequently deflecting said deflected one end of the ribbon along the edge of said stack backwardly toward said probe, sealing bar means on the opposite side of the stack of sheets from said deflecting means and'including two cooperating sealing bars, means for withdrawing said probe from said apertures, and means moving at least one of said sealing bars to seal the deflected end of said ribbon with a portion of said ribbon projecting immediately beyond said probe subsequent to withdrawal of said probe from said stack to thereby provide a sealed loop binding said sheets together.

2. Apparatus for binding a stack of sheets each having at least one perforation therein adjacent an edge thereof, a support for said stack, supporting the stack of sheets with the perforations in aligned relation with respect to each other, probe means insertable in the perforations of said stack of sheets for guiding a non-self-supporting heat scalable plastic ribbon upwardly through said stack of sheets, means feeding a ribbon of said material through said probe means to project said ribbon through said probe means beyond one side of said stack, means slidable along said one side of said stack for laterally deflecting the projecting end of the ribbon toward the edge of said stack, said deflecting means being operable to pass beyond the edge of said stack and downwardly thereover to deflect the deflected end of the ribbon backwardly toward said probe, means subsequently deflecting said deflected one end of the ribbon along the edge of said stack backwardly toward said probe, sealing bar means spaced from said probe means beneath said support, means for withdrawing said probe means from said apertures, and means moving said sealing bar means to seal the deflected one end of said ribbon with the portion of said ribbon projecting immediately above said probe means subsequent to withdrawal of said probe means from said stack to thereby provide a sealed loop binding said sheets together.

3. Apparatus for binding a stack of sheets each having at least one perforation therein adjacent an edge thereof, a support for said sheet, probe means insertable in the perforations of said sheet for guiding a heat-sealable ribbon upwardly through said stack of sheets, means ejecting a ribbon of said material through said probe to project said material beyond one side of said stack, means slidable along said one side of said stack for laterally deflecting the projecting end of the ribbon toward the edge of said stack, said deflecting means being operable to pass beyond the edge of said stack and downwardly thereover to deflect the deflected end of the ribbons backwardly toward said probe, means subsequently deflecting said deflected one end of the ribbon along the edge of said stack backwardly toward said probe, sealing bar means, means for withdrawing said probe from said apertures, means moving said sealing bar means to seal the deflected one end of said ribbon with the portion of said ribbon projecting immediately above said probe subsequent to withdrawal of said probe from said stack, and means for cutting said ribbon ends between the end of said probe and the point of sealing to thereby provide a sealed loop binding said sheets together.

4. Apparatus for binding a stack of sheets each having a plurality of perforations therein adjacent an edge thereof, a support for said stack, probe means insertable in the perforations of said sheets for guiding a heat-sealable ribbon through said stack of sheets, means ejecting ribbons of said material through said probes to project said material beyond one side of said stack, means slidable along said one side of said stack for laterally deflecting the projecting ends of the ribbons toward the edge of said stack, means subsequently deflecting said deflected ends of the ribbons along the edge of said stack backwardly toward said probes, sealing bar means, means for withdrawing said probes from said apertures, and means moving said sealing bar means to seal the deflected ends of said ribbons with a portion of said ribbons projecting immediately beyond said probes subsequent to withdrawal of said probe from said stack to thereby provide a plurality of sealed loops binding said sheets together.

5. Apparatus for binding a stack of sheets each having at least one perforation therein adjacent an edge thereof, a support for said stack, probe means insertable in the perforation of said sheet for guiding a heat-scalable ribbon upwardly through said stack of sheets, means ejecting a ribbon of said material through said probe means to project said material beyond one side of said stack, means slidable along said one side of said stack for laterally deflecting the projecting end of the ribbon toward the edge of said stack, means subsequently deflecting said deflected one end of the ribbon along the edge of said stack backwardly toward said probe means, sealing bar means including a stationary sealing bar beneath said support and the stack of sheets thereon and spaced along said support and the stack of sheets thereon beyond the perforations therein and a movable sealing bar spaced from said support and the stack of sheets thereon on the opposite side of the perforations in the stack of sheets from said stationary sealing bar, means for withdrawing said probe means from said apertures, and means moving said movable sealing bar toward said stationary sealing bar to seal the deflected end of said ribbon with a portion of said ribbon projecting immediately above said probe means subsequent to withdrawal of said probe means from said stack to thereby provide a sealed loop binding said sheets together.

6. Apparatus for binding a stack of sheets each having at least one perforation therein adjacent an edge thereof, a support for said sheet, probe means insertable in the perforations of said sheet for guiding a heat-sealable ribbon upwardly through said stack of sheets, means ejecting a ribbon of said material through said probe to project said material beyond one side of said stack, means slidable along said one side of said stack for laterally deflecting the projecting end of the ribbon toward the edge of said stack, said deflecting means being operable to pass beyond the edge of said stack and downwardly thereovcr to deflect the deflected end of the ribbons baokwardly toward said probe, means subsequently deflecting said deflected one end of the ribbon along the edge of said stack backwardly toward said probe, sealing bar means, means on said bar for simultaneously sealing the said one end of said ribbon with the portion of the ribbon projecting above said probe and cutting the ribbon ends to thereby provide a sealed loop binding said sheets together.

7. An apparatus for binding a stack of sheets perforated along one edge thereof with non-self-supporting ribbons of heat sealable plastic material comprising a support for a stack of sheets, abutment means on said support abutting the edge of the stack of sheets adjacent the perforations therein, linearly guided probe means insertable in the perforations of the stack of sheets for guiding the heat sealable plastic ribbons through the perforated portions of the stack of sheets, means for linearly moving said probe means into and out of registry with the perforated portions of the stack of sheets, feeding means operable when said probe means are in registry with the perforations of the stack of sheets for feeding the plastic ribbons through the perforated portions of the stack of sheets, displacing fingers engageable with the top of the stack of sheets and movable therealong toward said abut ment means and downwardly over the edge of the stack of sheets for deflecting the projecting ends of the ribbons beyond the edge of the stack of sheets and downwardly along the edge of the stack of sheets, sealing bar means beneath said table and including two cooperating sealing bars, a stationary of which is spaced from said probe means beneath said support and inwardly of the perforated portions of the stack of sheets supported thereon, the other of said sealing bars being movable and spaced on the opposite side of said probe means from the stationary of said sealing bars, means for moving the movable of said sealing bars to deflect the ends of the ribbons together, and means for applying heat to at least one of said sealing bars to provide sealed loops binding said sheets together and to trim said sealed loops.

8. In an apparatus for binding a stack of sheets perforated along one edge thereof with non-self-supporting ribbons of heat sealable plastic material comprising a support for supporting a stack of sheets, abutment means on said support abutting the edge of the stack of sheets adjacent the perforations therein, linearly guided probe means insertable in the perforations of the sheets for guiding heat sealable plastic ribbons through the perforated portions of the stack of sheets, means for linearly moving said probe means into and out of registry with the perforated portions of the stack of sheets, said probe means each having a feed roller rotatably mounted thereon for bodily movement therewith and engageable with the ribbon guided therethrough and maintaining the ribbon in position in said probe means for movement therewith, means for rotatably driving said rollers only when said probe means are in registry with the perforations in the stack of sheets for feeding the plastic ribbons through the perforated portions of the stack of sheets, displacing fingers engageable with the top of'the stack of sheets and movable therealong toward said aligning means and downwardly over the edge of the stack of sheets for de fleeting the projecting ends of the ribbons beyond the edge of the stack of sheets and downwardly therealong,

sealing bar means beneath said table including a stationary sealing bar spaced from said probe means inwardly of the perforated portions of the stack of sheets and a movable sealing bar on the opposite side of said probe means from said stationary sealing bar mounted for cooperative movement with respect to said stationary sealing bar, means for moving the movable of said sealing bars to deflect the ends of the ribbons together into engagement with the stationary of said sealing bars, and means for applying heat to at least one of said sealing bars to provide sealed loops, binding said sheets together and to trim said sealed loops.

References Cited in the file of this patent UNITED STATES PATENTS 2,200,877 Farkas May 14, 1940 2,273,824 Barrett Feb. 24, 1942 2,358,062 Farkas Sept. 12, 1944 2,571,525 Blitstein Oct. 16, 1951 2,930,054 Bardy Mar, 29, 1960 FOREIGN PATENTS 157,636 Australia Mar. 20, 1952 

